SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b460516343546d9e6241a7c10fbf2b4a8a46ae6c5f4edbe26ebb5b4705baa686' 
  AND token = 'GyORsjoqbCzb2fl/zyPBuLXZYXRcKbK9DxfMUk44Qbg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}